25% is very low humidity. Surely you mean more like 75%. In England milk was kept cool in pre-fridge days by standing it in a saucer of water, and then covering it with a bell-shaped unglazed earthenware pot that stood in the water. Evaporation did the job, in all weather conditions, so long as it was kept out of direct sun and the water wasn't allowed to run dry.

When I saw Jesse's post I was going to post, well you just made Wade's point, but decided not to. Now that he has posted the chart, he still doesn't understand that we would not be comfortable at 85 (down from 100) with 40% humidity. Living in the low desert, probably 50% of the population uses swamp coolers until it hits about 25% humidity, so I totally get your post.

Jesse, you would have to experience evaporative cooler to know no matter what your chart shows, it doesn't fly. It is a little like the poster saying that no one bone fishes in SP because he read it somewhere. I don't even turn on the A/C until it is over 100 here in Palm Springs.